Improvement w hot-air furnaces



Le n. IISATTERLEE.

Ht-r

Furnaces.

UNITED STATES PATENT OFFICE.

LE nov sATTEELEE, or ROCHESTER, NEW YORK.

i |MpRovEMl-:NT iN Hor-'AIR Fu-RNACES- Specification forming part of Letters Patent No. 152,693, dated June 30,1874; application filed May 9, 1574.

To all 'whom t may concern:

Be it known that I, LE ROY SATTERLEE, of the city of Rochester, in the county of Monroe and State of New York, have invented a certain new and useful Improvement in Furnaces; and I do hereby declare that the following is a full, clear, and exact description of the con# struction and operation of the same.

This invention relates to hot-air furnaces having drums at the top and bottom connected by vertical flues, arranged to produce a zigzag current in a direction reverse to the draft. The improvements are hereinafter described.

In the drawings, Figure lis a vertical section in line ac of Fig. 2. Fig. 2 is a horizontal section in line y y of Fig. 1, looking downward. Fig. 3 is a similar section in line z z, looking upward.

This furnace may be made from wrought or cast iron, or a combination of the two, and -it is inclosed in the usual outer casing A, which may be sheet metal or brick. The furnace proper consists of the following parts: B is the base, on which rests the firechamber G extending centrally to the top of the furnace, where it is closed. It is provided with the usual grate andan iron or fire-brick lining at the bottom to prevent burning out. D D are twoV drums or air-spaces surrounding the fire-chamber, one being situated at the bottom and the other at the top. The bottom one, however, is cut away or notched, as shown at b, Fig. 3, sufficiently to admit the chute, which vopens into the fire-chamber 'for the iusertion of the fuel. 1, 2, 3, 4, 5, 6, and 7 are a series of vertical draft or heating tubes surrounding the fire-chamber and connecting the two drums'. They open simply through the lower plate ofthe upper drum and the upper plate of the lower drum, as shown. They are arrangedy at suitable distances apart, and on the front side an interval is left corresponding with the space b, in which the draft-tubes are notused. G G and G G are division plates or diaphragms across the interior of the drums. In the `upper drum two of these plates inclose a single draft-tube space, as shown at d, and this space communicates Awith the top of the tire-chamber bya tube, f, so that the draft from the fire-chamber passes to the draft-tube marked No. 1. Theother division-plates are made to inclose the space of two of the drafttubes each, as shown. The division-plates of th e y lines Fig. 2 and black lines Fig. 3, and at the end of the` circuit, adjoining the space d, two of the plates incloseV a similar space, d', einbracing a single draft-tube, and from this space a tube, g, passes into the fire-chamber, just above the re-po-t, and there communicates with an exit-pipe, H, which rises through the interior of the fire-chamber and passes through the top of the furnace to the chimney. The division-plates may be made either stationary or movable; and, if desired, they may be fixed. in the form of valves which. can be turned from the outside. 'A cleaning device may also be located in the drum-space,for the purpose of removing ashes.- I IV are air-tubes passing vertically through the draft-tubes and opening through the upper and lower plates of the drums, as shown, and serving to conduct the air from the lower air-space h to the 'domespace k. A jacket-space is left between the air-tubes and the heating or draft-tubes to allow a free passage to the draft all around the air-tubes.

The operation is as follows: The heat from the rechamber passes from the top of the same through the tube j' to the space d, and, finding no other exit, dives down through heating-tubeNo. 1. In the bottom drum it strikes the division-plate and rises through 2. It alternately rises and falls through these tubes till it arrives at the bottom of v7 in the space d', when, having no other exit, it passes through g, and, finally, escapes through the exit-pipe II to the chimney. In passing the blank b in the top drum the draft passes through a closed space in the upper drum, in which no heating-tubes are used, but having the air-tubes I I, as shown at the left in Fig. 2.

By the means above described the air inclosed by the outer case A obtains the 'direct radiation of the heat from the fire-chamber, which it surrounds, and it also obtains the exterior radiation from the heating-tubes 1, 2, 3, 4, 5, 6, and 7; and in addition to this it obtains the internal heat of the tubes 1, 2, 3, 4, 5, 6, and 7 by the passage of the air-tubes I I through the same. An advantage is gained in the zigzag or indirect passage of the draft through the heating-tubes, by which a long and circuitous route is obtained, during which time the heat is expended both externally and internally upon the air. This exposes a much greater heating-surface than in ordinary furnaces. An important feature, also, consists in the employment of the exit-pipe H, resting directly in the interior of the tirechamber, or

in an oi'set or auxiliary chamber of the same, by which means an active draft is produced by the action of the ire on the exit-pipe. To produce proper action in the indirect passage through the draft-tubes, some accelerating action is required, otherwise the draft would deaden in so long a circuit. The re coming in contact with the exit-pipe will so stimulate the current that no difficulty can arise from deadness of the draft. A valve or damper may be used, covering an opening in the exitpipe Within the fire-chamber, for the purpose of allowing a direct draft for kindling the fire or in starting the same when low.

The exit-pipe, instead of being situated directly in the lfire-chamber, as above described, might be located in a chamber or oifset from the same, or otherwise arranged to receive the heat to produce an active draft.

In the vbottom of the exit-pipe H is a cone, m, which opens through the bottom, but is closed at the top, and extends up some distance within the exit-pipe, as shown. Its object is to collect and concentrate within the exit-pipe a portion of the heat of the firechamber, so as to produce a more active rarification of the draft within the pipe. By this means the air within the pipe must pass in a thin sheet between two highly-heated surfaces, lwhich imparts additional force to the ascending current.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

In combination with the-ire-chamber C and heating-hues l, 2, 3,' 4, 5, 6, and 7, connected by the tubes fg, the exit-pipe H resting directly within the fire-chamber, or in an auxiliary heating-chamber, for the purpose of accelerating the draft, as shown and described.

In witness whereof I havevheierunto signed my name in the presence vof two subscribing witnesses.

LE ROY SATTERLEE.

Witnesses: y

EUG. H.- SATTERLEE, R. F. OsGooD. 

